Imidazole derivatives and process of preparing the same



Patented Oct. 31, 1 944- UNITED STATES PATENT OFFICE- IMIDAZOIiE DERIVATIVES ANDPROCESS F PREPARING THE SATME Charles Graenacher, Riehen, and Jost Frei, Basel,

Switzerland, assignors to Society of Chemical Industry in Basle, Basel, Switzerland, a flrm No Drawing. Application March 25, 1941, Serial No. 385,200. In Switzerland April 8, 194d (Jlaims.

In U. S. application Serial No. 335,136, filed May 14, 1940', it has been shown that new derivatives of heterocyclic compounds are obtained if imidazoies of the general formula in which :1: represents an aromatic nucleus containing at least one sulfonic acid'group, R1 and R: represent hydrogen or a substituent, or their salts are treated with alkylating or aralkylating agents; and, if desired, at any desirable stage of the reaction, further optional alkylating or aralkylating agents, which differ from the alkylat ing or aralkylating agents mentioned, are allowed to act upon the reaction compounds. Amon other substances,'alkyl'ene oxides may be used as alkylating agents in this process. More exactly described, however, is the reaction of alkylene oxides with those imidazole sulfonic acids (or salts thereof) which contain at least one hydrogen atom belonging to an amino or imino group or toa hydroxyl group united to carbon.

It has now been found that, in a surprising manner, valuable derivatives of heterocyclic the general formula compounds areequally obtained if imidazoles of inwhich :1: represents an aromatic nucleus containing, if desired, a free or neutralised sulfonic its homologues and analogues, such as o-toluylenediamine, or from 0- or 1:8-naphthylenediamine. In these imidazoies, the substituent R1 may represent, for example, a hydrocarbonradical, such as an alkyl 'or varaliryl radical, The substituent R1 may, however, also stand for a hydrocarbon radical which is substituted, or the chainof which is interrupted by hetero-atoms, such as oxygen, sulfur, or nitrogen atoms, or by atomic groupings containing-such atoms. ,The

substituent R2 in the above formula may repremethyl- -undeeylbenzimidazole sulfonic acid,

acid group and R1 and R: represent substituents,

. and in which no hydrogen atom belongs to an amino or imino group or to an hydroxyl group combined with carbon, are treated with 1:2-

alkylene oxides or their substitution products.

As imidazoies of the general formula in which :r, R1 and Re have the meaning given above, may be used, for example, benzimidazoles and naphthimidazoles substituted at the-l-nitrogen atom and the 2-carbon atom and their sulfonic acids, in which no hydrogen atom belongs to an amino or an imino group onto a hydroxyl group combined with carbon, and which, for example, are derived from o-Dhenylenediamine or benzyl- -heptadecylbenzimidazole sulfonic acid,

N-dodecylr-propylbenzimidazole sulfonic acid.

The products of the formula z\ CBa N i J wherein :c, a; and R2 have the meaning indicated above may also be designated as uand N-substituted imidazoies sulfonated if desired which are free from hydrogen atoms bound to nitrogen atoms or to oxygen atoms adhering to carbon atoms and in which the two imidazole nitrogen atoms are united with .two carbon atoms in ortho position of an aromatic nucleus. I

Especially valuable products are obtained if as, I

starting materials imidazoies of the formula N/ A I 1 wherein a: standsfor a radical of the benzene series containing a neutralised sulfonic acid group, Ristands for an alkyl radical, R2 stands for an alkyl radical containingat least 11 carbon atoms and wherein at, R1 and-Ra are free from hydrogen atoms bound to nitrogen atoms orto oxygen atoms adhering to carbon atoms, are

mula

wherein :1: stands for a radical of the benzene series containing a neutralised sulfonic acid group, R: stands for an odd number of carbon atoms between -20, and wherein a: and R: are free from hydrogen atoms bound to nitrogen atoms or to oxygen atoms adhering to carbon atoms.

1:2-alkylene oxides and their substitution products which come into consideration for the present processes are, for example, ethylene oxide, propylene oxide, glycides, as well as glycidic acid esters. Glycidol and esters of glycidic acid are examples of l:2-alkylene oxides containing a reactive substituent. 1

The reaction between the imidazole compounds andthe 1:3-alkylene oxides is preferably to be carried out at raised temperature, for example, at

' 100-150 c. when easily volatile allwlene oxides used. Examples are the imidazoles of the for-- are used it is generally preferable to work under pressure. It is particularly advantageous if an excess of 1:2-alkylene oxide or its substitution product, for example, 4-8 molecules for every molecule of the imidazole compound, be used for the reaction.

The reaction products obtained by the present process, so far as they are water-soluble and are derived from suitable parent may be used as textile auxiliary products, !or example,

as wetting, cleansing, washing. emulsifyin dis-- p r-sing, foaming, softening, and levelling agents. For these purposes, those reaction products of imidacole compounds are particularly suitable which contain an aliphatic or cycloaliphatic radical of high molecular weight at the n-carbon atom or at the N-atom. such products can form valuable productsforuse inthedyeingof wool. in

, many cases, in particular in the case of dyestuffs which contain metal in complex union, deeper and bloomier shades are yielded by the use of suitable products of the invention in the dyein process.

The water-soluble products of the invention are to be distinguished from the parent imidazole compounds by an increased stability towards acids or an, increased dispersing power with re-.

gard to sparingly soluble organic sulfonic acids in acid'solutions.

The chemical constitution of the products obtainable according to the present invention could not be ascertained with certainty. Therefore the best'characterised by their process products are In case more than two mols of oi manufacture.

an lzz-alkylene oxide are used, ether radicals are introduced into the imidazole molecule, a hydrogen atom bound toa carbonatom being probably the ether radical. Since the hydroto thecarbon atoms occupying substituent are especially that such a hydrogen replaced by gen atoms bound the -position of the reactive we may assume thefnumber of mols of ethylene oxide that has been used). when the imidazole derivative is atom is replaced by an ether radical, for instance.

ted viscose material, a dyebath is prepared at 40-50" C. containing 0.25% ofDirect Sky Blue green per litre of the product described above, obtained treated with at least two mols of slyeicol, polyelycerol radicals are introduced into the molecule.

The products obtainable according to thepresent invention may be used alone or in combination with other substances, such as salts, par

Example 1 25 parts of the sodium salt of sul fonated N- methyl-p-heptadecylbenzimidazole having the formula NaOsS N are heated in an autoclave fitted with stirrer with 22 parts, i. e., with about 1'0 molecules, of ethylene oxide-at -140 C. until all the ethylene oxide has been taken up. The resinous reaction product, which is brownish in colour, and which may be stirred whilst hot, solidifies on cooling-to give a solid mass which is readily soluble in water with a neutral reaction and yields a" capillary active solution. when used in neutral and alkaline dye baths, the product possesses exceptional levellin properties and gives a pleasant, soft handle to textiles treated with it.

In a similar manner, the sodum salt of .N- methyl- -undecyl-benzimidazole sulfonic acid, of the formula C-Cufiu NBC-MB may be caused to react with about 10 molecules of ethylene oxide'to yield a valuable textile auxiliary product. The product thus obtained is a solid substance easily soiuble'in water to form a neutral,capillary active solution. 7

Further, the alkali salts of sulfonated N-benzyl-, or N-ethyl- -heptadecylbenzimidazole, or of sulfonated N-cyclohexyl- -heptadecylbeuzimidazole, or of the sulfonated N-methylated benzim'idasole shade (Colour Index no; 51a) and 0.3 grain from the sodium salt of sulfonated N-methyla-heptadecylbenzimidazole. The material is entered into the dyebath, which is heated as usual until almost boiling, and dyeing is continued at sodium salt of sul- 1 assure this temperature for /z-l hour. The addition of the product mentioned causes the dyestuff to be absorbed slowly and evenly by the material and thus yields a more'level dyeing than if the operation 'be carried out without this addition.

At the same time, the material receives a pleas- NaOaS N are pasted up with parts, i. e., about 4'molecules, of glycidol and, whilst stirring, are gradualis; heated to 110 C. The mixture thus becomes a thin-flowing liquid, and a reaction sets in which causes lively evolution of heat. It is preferable to maintain the mixture at the temperature stat-- ed byaexternal cooling. When the heat generation has finished, the reaction mixture is stirred for 1 hour at 120-130 C., a yellowish brown reaction product being obtained which may be stirred whilst still hot but which becomes viscous on cooling to room temperature. This product gives a clear solution in water, showing a neutral reaction; the solution possesses capillary activity. In contrast to the parent material, the new product is not precipitated from its solution even by mineral acids. v

In place of theglycidol mentioned above. a glycidic acid ester can be used. Further, glycidol may be allowed to react, in a similar manner,'

with the imidazole derivatives mentioned in Example l, instead of with the sodium salt of sulfonated N-methyl- -heptadecylbenzimidazole.

What we claim is:

1. A process for the manufacture of an imidazole derivative, which comprises reacting with each other, as sole reactants, at least one mol of a member of the group consisting of unsubstituted 1:2-alkylene oxides, hydroxy 1:2-alkylene oxides, and esters of carboxy 1:2-alkylene oxides, and a sulfonated ,uand N-substituted imidazole which is free from hydrogen atoms bound to nitrogen atoms and is free from hydroxy groups bound to carbon atoms and which contains the free trivalent nitrogen group N in the imidazole ring, both nitrogen atoms of the latter being trivalent.

2. A process for the manufactureof an imidazole derivative, which comprises reacting with each other, as sole reactants, at least two mols of a member of the group consisting of unsubstituted 1:2-alkylene oxides, hydroxy lzz-alkylene oxides, and esters of carboxy 1:2-alkylene oxides, and an imidazole which contains the free trivalent nitrosen group N= in the imidazole ring andwhich corresponds to the formula carbon atoms, R1 stands for an alkyl radical,

and Ba stands for an alkyl radical containing at least 11 carbon atoms, both nitrogen atoms of the imidazole ring being trivalent.

34 A-process for the manufacture of an imidaz vole derivative, which comprises reacting the imidazole of the formula -CuHra NaOrS N with 10 mols of ethylene oxide.

4. A process for the manufacture of an imidazole derivative, which comprises reacting the imidazole'of the formula I I CH: 1

C-GnHu NaOrS N with 10 mols of ethylene oxide. I

5. A process for the manufacture of an imidazole derivative, which comprises reacting the imidazole of the formula 6. A sulfonated imidazole derivative obtained by reacting with each other, as sole reactants, at

least one mol of a member of the group. consisting of unsubstituted 1:2-alkylene oxides, hydroxy 1:2-alkylene oxides, and esters of carboxy 1:2-alkylene oxides, and a s'ulfonatd andv N-substituted imidazole which is free from hydrogen atoms bound to nitrogen atoms and is free from hydroxy groups bound to carbon atoms and which contains the free trivalent nitrogen group -N= in the imidazole ring, both nitrogen atoms of the latter being trivalent said derivative being, in the form of its alkali metal salt, a viscons to solid substance which is easily soluble in water to form a neutral capillary active substance. '7. A and N-substituted imidazole derivative which contains a neutralized sulfonic acid group and at least one ether radical, which derivative is obtained by reactingwith each other, as sole reactants, at least two mols of an unsubstituted 1:2-alkylene oxide and an imidazole which contains the .free trivalent nitrogen group -N,=, in the imidazoie ring and which corresponds to the formula Br I N X :C-B:

wherein 1: stands for a radical of the benzene series which contains a neutralized sulfonic acid group and is free from hydroxy groups bound to carbon atoms, R1 stands for an alkyl radical, and Rs stands for an allwl radical containing at least 11 carbon atoms, both nitrogen atoms of the imidazole ring being trivalent, said derivative being,

in the form of its alkali. metal salt, a viscous to solid substance which is easily soluble in water to form a neutral capillary active substance.

8,. The aand N-substituted imidazole deriva- 4- I assure tivc containing a neutralised sulionic acid group and at least one polyglycol radical, which imidazole derivative is obtained by reacting the imidazole oi the formula (i-Crim- NIO: i

with 10 mois oi ethylene oxide and is a solid substance easiw soluble in water to form a neutral capillary active solution and excellent equalizing andgsoitening properties.

9. The nand H-substituted imidasole derivative containing a neutralised sulionlc acid group and atleast one pciyglycoi radical, which imidasole derivative is obtainedby reacting the imidaaole oi the formula I (iJHs N b cnal NaOaB with 10 mole of ethylene oxide and is a solid substance easily soluble in water to form a neutral capillary activesolution. v

10. The nand N-substituted imidazole derivaii tive containing a neutralised sulionie acid group and at least one polyglyccrol radical. which imidaeole derivative is obtained by reacting the imidarole oi the formula cmnms cmmmcnmr Joe-r mm. 

